local installation using xampp not working

I’ve had wordpress successfully installed on my PC using xampplite. First installation was successful and I’ve been happily playing with wordpress. I recently went into the xampplite files and changed my database security status buy putting in a password, and now can’t get wordpress to launch, and can’t remove the password in xampplite. WordPress says “Error establishing a database connection”. I’m out of my depth here and can’t see what to do next.